- Physics world. - Hello and welcome to the
Physics World Weekly Podcast. I'm Hammi Johnston. In this episode, we meet an
ion source expert at the UK's National Physical Laboratory,
who talks about her passion for building scientific instrumentation. And we also chat with an
astrophysicist whose work on dwarf galaxies has helped us hone in on the properties of dark matter. But first, a word from our sponsor. Sir, this podcast is supported
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has been a reliable partner for universities, laboratories, and industrial players all over the world. Find out more@raconvacuum.com. Lilly Ellis Gibbons is a
higher scientist at the UK's National Physical
Laboratory in Teddington, which is on the western edge of London. She did an undergraduate
physics degree in Australia before working for several years as a science communicator in schools. She then did a PhD in atomic and molecular physics at Spain's Institute of Fundamental Physics in Madrid after a stint at
University College London. Lily joined NPL in 2021, where she works on a wide range of instrumentation technologies. Hi, Lily. Welcome to the podcast. - Hi. Thanks for having me. - So Lily, you've developed
instrumentation in a, a wide range of applications. How did you first become
interested in working in the field? - I mean, it was kind of serendipity because in the final year of
my undergraduate, I had to do a internal project with a
professor at the university. And I was just looking around and I chose one that worked
in fundamental atomic and molecular collisions. And this is sort of homemade equipment, all vacuum equipment, and the instrumentation is quite intense, and I enjoyed that. But when I finished my
honors year, I was looking for a PhD in Australia and I actually went on a road trip with another graduate friend of mine, and we visited the universities and chatted to different people, and I couldn't find
something that really fit. And so I did that work as a science communication
officer, which was really great. But at some point I was
thinking, okay, I'd really like to get back to something more scientific and a little more challenging. And, uh, my professor who had
I had done that project with, happened to know someone
who was offering a PhD in Spain in similar work. So I was very lucky to be in the right place at the right time and looking for something, uh,
challenging and scientific, and that I had already done
this one project, uh, working with vacuum instrumentation. And I just really enjoy
knowing how things work. And I really love
instruments that can take what is an incredibly complicated world and break it down into smaller and smaller pieces until you
can say something extremely fundamental about what's going on. - And your PhD in, in Spain
involved the development of new ion sources for radiotherapy. Can you talk a bit about this research? What was the goal there? - Yeah, absolutely. Um, it was part of a Marie Curie International
Training Network under the FP seven funding group. And the project was called argent, which was advanced radiotherapy generated by exploiting nano technologies. And this was quite a large
project that involved, uh, 13 different students across a number of institutes across Europe. And the institute I was
at in Spain was sort of the fundamental physics branch of this. What the project was looking
at was how, uh, radiotherapy and nanoparticles can
intersect in treatment. It was focused on ion therapy
as a radiotherapy technique. Ion therapy is where you
use ions like protons or, uh, something a little
heavier like carbon plus ions in the body to help to destroy tumors. And this works, uh, very well
in some cases, particularly for things like brain
cancer and spine cancer because when you use ions for
this type of radiotherapy, instead of depositing the energy all the way along the
pathway through the body, so you'll have sort of roughly
the same energy deposited, you know, as it enters the
front of the chest compared to when it enters into the
tumor itself deeper in the body. When you use ions for radiotherapy, you have something called the brag peak where the energy is mostly deposited, uh, at a certain depth into its path. And so this means that you
can have really high intensity energy deposited straight into the tumor. And this is really, really
excellent for deep-seated tumors. And the project I was
working on was looking at how when you have this ion therapy, you are not just shooting these high energy ions into the body. You're actually creating
with that as a cascade of lower energy particles. You have electrons, you have
other ions you're creating and you have radicals. And these all affect the
cells that you're targeting and they can affect them in
lots and lots of different ways. We were trying to develop
iron sources that could basically show us a very basic system of those secondary created
particles from the initial iron beam with molecules that
you might find in the body. And we focused on things like DNA bases. Uh, we were effectively trying
to make beams of radicals and of different types of ions, and also we had electron
beams in the lap as well. - W when you're making those beams, or are you trying to
understand what's happening inside the body by making relatively energetic beams,
um, that would, I suppose, be created during radiotherapy or, or is the idea to use
those beams in a in a radiotherapy setting, - Uh, is certainly more to
understand what's happening? So it, uh, produces the kind
of data that you can use for modeling radiotherapy really well. Um, so to improve models
from being, for example, considering the body to be just water. If you want it to be a more complex and more complete model, you also want to include things like
DNA, um, and proteins and to include those higher mass molecules and more realistic
molecules in your models. You need a lot of data to
understand how they interact with the components of the radiotherapy
trail through the body. Um, and it's also quite
valid in terms of looking at how different cells go through cell death. Um, there was a lot of research done in the early two thousands
around, um, electrons and how they interact with DNA. And it was actually found
that electrons with very, very low energy, you know, like, um, a hundred thousand times less
energy than the proton beam itself can actually disrupt DNA
enough to cause it to break. And this kind of process can, uh, obviously kill the cancer cells that you're interested in killing if you, if you damage the DNA enough,
those cells can't survive. Um, so we were interested
in producing data to make these models of
radiotherapy systems, but also in understanding the chemistry of what's going on within the cells and how that might be better utilized in radiotherapy treatment. - I see. And and it
sounds like that, I mean, that must be a real challenge because you're, you must be dealing with some fairly complicated molecules and and chemistry in your, in your
ion source, how it, I mean, it sounds to me that it
must be very difficult to actually get the
ions out that you want. - Yeah, I mean, in this
case we were trying to work with quite simple systems. I think I did quite a lot
of work with oxygen, um, and plasmas trying to make a beam, uh, of oxygen radicals or
negatively charged oxygen ions because, uh, as there's quite
a lot of water in every cell, you're going to be, uh, having a lot of oxygen based radicals and ions. And this can then interact
with something as small as a molecule, uh, with
say six or seven atoms. So you can build the
system to be relatively simple, but it's still quite
difficult to get what you want. Um, plasmas are very complicated things, and depending on how you
are making your plasma and how you're extracting
the different parts of the products of that plasma,
it can really, uh, change how you can produce enough of the ion of interest, for example. - I see. Lily, when I was
looking at your, at your cv, I, I also noticed that you'd
worked in experimental astro chemistry and I was sort
of scratching my head how, you know, how how did she
get from radiotherapy to, to astro chemistry, but I
think I understand it now. Is it were, were you looking
at the sort of chemicals that could evolve in space
in Mm-Hmm, in, in sort of ion, you know, as
ions in, in a vacuum chamber? - Yeah, yeah, for sure. Astro chemistry is a super
fun field. I really loved it. Um, it is definitely looking at what kind of chemistry can happen in
different parts of space, and it sounds very different to looking at how radiotherapy interacts with the body. But in terms of the techniques
we used, it's quite similar. So you're using ion beams
and electron beams in vacuum, and you're looking at the
interactions of these beams with a molecule of interest. So in some cases, we would find something in the literature from spectroscopy. So people with the telescopes
would look at Titan, for example, and say, oh, we saw in the ionosphere
that there's this molecule. And we'd say, okay,
that's very interesting. What happens, um, in that
environment to that molecule? Does it break down?
Could it form new bonds? Could it turn into, for
example, a singly charged or a doubly charged ion? Um, and so yeah, we end up
using similar techniques for a very, very different application. - I see. And I, I suppose when,
when I see astro chemistry, I, I immediately make the leap
to astrobiology and mm-Hmm. , you know, the,
the looking at the chemistry that could occur on, on distant planets and lead to the, the emergence of life. Is that, is that something
that, that you look at as well or looked at as well? Or is that sort of a bit
further down the road from the research that you were doing? - That is certainly, um, a
point of interest for us. It's huge in astro chemistry. Uh, a biogenesis is really fascinating, and one of the reasons that we would choose certain
molecules to investigate is because of their potential to
do chemistry that would lead to something like an amino acid. And for example, I would
work with molecules that had CN bonds because that's really
important in, uh, the kind of chemistry that happens inside life. And we also looked at, um, I
don't know if you remember, but there was, I think pH
three potentially discovered in the atmosphere of Venus. Oh, - That's right. Yeah, - Yeah. And everyone was very excited because that's really only
produced in certain kinds of processes that involve
biology, uh, for example, the rotting of natural matter. Um, so we also investigated
pH three as well, just to see. Okay. Um, unfortunately, after further analysis
of that telescope data, they discovered that the likelihood of pH three being there is
actually very, very low. Um, but we still did some
research to see, okay, if you had it in the ionosphere or if you had it in
the interstellar medium or in a nebula, um, it's in
this environment that has a lot of electrons or has a lot of ions or radicals, what happens when
you interact this molecule with this energetic species? - I mean, it sounds like
a very exciting field because, um, I suppose
you've got chemists, you've got physicists, you've got astronomers all working together. Did you, I mean, did you
find it very rewarding? I'm guessing you probably
learned lots about planetary physics and, and things like
that while you were doing it? - Yeah, I definitely learned
a lot. It was, uh, very fun. The conferences are always fascinating and they have wonderful
pictures in all of their talks because of course, you can just
produce these amazing images from telescope data. Um, the, uh, overlap between the people doing astro chemistry and the people doing sort of,
uh, you know, planetary motion and gravity and things
like that is a lot smaller. Um, but definitely we spoke
to a lot of physicists who are modeling, you know,
what the concentrations of different atoms in different parts of the universe should be. Uh, so this, this was always really great. - And in, in 2021, you
joined NPL, and you're, and you're a higher scientist there. Can, can you give us an idea
of what your job entails and, and maybe describe some of the projects that you're working on at the moment? - Yeah, absolutely. Um, so I
joined a group called NICE MSI, which is, uh, a mass
spectrometry imaging group. And our group mostly works on, uh, chemical imaging of surfaces. And a lot of what we
do is biological based. So again, this is, uh, quite
a different field in terms of what we are like looking at practically, but the instrumentation,
again, is relatively similar. Um, so it's, again, it's high vacuum work and it's, uh, developing ion sources. Now, the cool thing that I'm doing now is that I'm working on ambient ion sources. So, um, when you have
a sample that you want to look at with mass spectrometry
imaging, you often have to put it in the vacuum
or you have to coat it with something, or you have
to, uh, wash it several times. Um, so for example, if we're
looking at, you know, uh, tissue samples, um, one of the techniques that we use here is called
maldi, which is, uh, requires the use of a matrix
to allow for the transfer of energy from a laser beam
into the material in the sample to then allow it to be ionized and detected by your mass spectrometer. But some samples can't
really go in the vacuum and some samples you don't
want to cope with something. So what I am looking at is how to look at these samples
just in air, just in the lab. And so I've got a few,
um, laser setups, uh, and we have a plasma
post ionization system. We have a few other types of
ambient techniques that have, for example, a, uh, spray of high voltage ethanol and water mixtures onto a surface. And what we're trying to do is, uh, analyze the different chemicals
that are in these surfaces and produce different
maps of these chemicals. I have a few projects that I'm working on. I particularly enjoy one where I'm looking at unusual sample types. So trying to use these ambient
ionization techniques on things like, uh, plant
matter or we had some insects or we had a collaboration
looking at different, uh, kinds of fabrics. You know, it's, it's all
quite varied and interesting, but again, it's, it's working
on the instrumentation. And since the National
Physical Laboratory is a measurement institute, we're also very interested in
making sure these techniques are quantifiable and
that they are repeatable and that we have really high
scientific integrity within the community as well. - And do, do you do most
of your work in Teddington? Or, or do, do you visit other facilities, maybe national labs in the UK or, or, uh, university labs, uh, that you might have collaborations with? - Uh, we have quite extensive
collaborations across the uk. We had a project recently with the Cancer Research UK
people, it was called Rosetta. And we were collaborating, uh,
across all sorts of different institutes like the
Rosalyn Frankland Institute and with different universities as well. Um, for the most part, we would do the work within our own labs and collaborate with them in terms of, uh, running studies across
the different systems. Um, 'cause obviously each lab can contribute something
different to the project. And also in terms of analyzing
the data in coherent ways. And I myself haven't done this, but NPL does have collaborations with the other measurement
institutes across the world. So, for example, NIST in the us Mm-Hmm. , uh, we have been, we have an exchange
program of sorts with them. So there are opportunities,
uh, to do that kind of work across the board, but mostly we collaborate by, uh, working on the projects
together from our own labs. - Wow. That, that sounds fascinating. You know, we might have someone
listening who's maybe just about to finish a, a
bachelor's degree in physics, and they're thinking, wow, you know, a, a career in instrumentation that sounds like it could be for me. What, what sort of advice
would you give to, to someone you know, at that point in
their career, if they'd like to work at a place like NPL or nist? Um, what, what, what should they be doing? - I think I would advise,
obviously getting time in a lab, trying to fix things, um,
with guidance, obviously, but actually spending that time by yourself working on
important problem solving skills is really vital. I would also say that
instrumentation in academia can be quite risky, because if you are on a
project to develop something that fails, it's very
difficult to then show that you have the background to be offered the next
fellowship or the next job. If you are in that situation,
then it's always good to have something, a side
project that trundles along and produces data as well, so
that you always have something to keep publishing and keep pushing. But there are jobs and instrumentation that
are outside of academia. So, I mean, the National Physical
Laboratory is an institute, and we are involved in
academia in a big way, but we're also involved
in commercial projects. And there are also the companies that produce the instruments
that scientists use, and they have some
really amazing scientists working in development there. Those can be really
excellent pathways as well. - I think earlier you, you
mentioned something about, you know, working in a lab where you were building equipment, I suppose rather than
using, you know, sort of off the shelf stuff. I mean, is is, is that an important thing to do early in your career to
actually have to sit down and, and maybe design a, a
bespoke piece of equipment and, I don't know, get the
soldering iron out, um, and, and put it together yourself? Is that, is that sort of a
crucial thing that one should do? - I think it's very
important, um, in terms of learning those fundamental
lab skills, learning how the electronics work, learning how to put together vacuum equipment,
learning how to model, uh, for example, in CAD or Fusion 360, um, you
will always, as usually as lab scientists, you'll be working with a machine engineering shop, so you'll want to be producing designs for them to make and then testing them,
and you'll also be having to put together things yourself. So I spent quite a lot of time, uh, and it actually taught me
how to stop being so clumsy. I spent a lot of time
putting together very tiny, very delicate things with little screwdrivers
while wearing gloves. And so now I'm at the point where I don't just put my tool
down and forget where it is, and I don't drop everything
that I'm holding, and I can be quite
careful when I need to be. And this is learned
through hours and hours and hours in the lab, putting together and taking apart the
instruments themselves. - Oh, that's interesting. And, and is that something that, that you did before you, you know, be, before you even started your
bachelor's degree in physics, you know, when you were younger, were, were you taking things apart
and putting them back together or maybe not putting them back
together, , um, or, or is that something that
you developed, you know, when you studied physics? - I think, I wouldn't say I was
that stereotypical idea of a scientist or engineer who's
like taking apart the toaster. Um, I have always been
fascinated by how things work, but that didn't necessarily
mean I always investigate my environment, but I wouldn't take something and pull it to pieces. Um, that was really something
that I developed a passion for through starting work in the lab. Hmm. Because I wanted to, I, I
want to know how things work, but I also really like machines
that are quite complicated that can do something that
you can't even see, you know, you can't see an electron beam. You, you have to imagine
it, you have to imagine how the electric fields are interacting with those charge particles. - Is that, is that something
that's important in your work? Is, is having, having the ability or the experience to imagine
what's happening in a system where you can't see it
either an el you know, an electronic system where you've got signals
going in all directions or in a, in an experiment, you
know, in your vacuum chamber, you can't just stick your
head in there and poke around. Um, is, is having a a good
imagination important? - Uh, I think it is. I think being able to, uh, not necessarily visualize the whole thing, but to be able to keep a lot of different factors in your
head at the same time is really important for experimentation. So if you are, because
these things are processes, and if you don't do everything
right in the right order, you don't get the results you expected, but you also want to
be able to think about what could be going wrong? Why am I not seeing signal here? Where are the points within
the instrument where I need to adjust the, the voltages
on this iron funnel? Or something like that. Like, what points can I change things in order
to get the result that I want? So I, I think being able to
at least understand, visualize and maintain sort of a catalog of what you're actually
doing is really important. - Well, that's great. Tha thanks. Some, some great advice
there for, uh, for up and coming instrumentation physicists. And, and thanks for
talking about your career. It's, uh, I mean, you've done
some fascinating stuff tha thanks for coming on the podcast, Lily. - Oh, you're welcome. Thanks
so much for inviting me. It's been fun. - Perhaps one of the biggest
measurement challenges facing physicists is nailing down
the properties of dark matter, an elusive substance that appears to influence large
structures in the universe. Here's physics world's
Margaret Harris in conversation with an astrophysicist who
is part of a collaboration that has helped constrain
theories of dark matter. - According to the best developed theories of modern cosmology, a
mysterious substance known as dark matter makes up 85%
of the mass in the universe. We don know this invisible
form of matter is there because it affects the
movement of stars and galaxies, but we don't know what it is and we don't have definitive
evidence of it interacting with normal everyday
types of matter either. What we do have, though, are
ideas and tantalizing hints. And here to talk about one of
those hints is Alex McDaniel, who as a postdoc at Clemson
University in the US was looking for evidence of dark matter and what's known as dwarfs
spheroid satellite galaxies. Hello, Alex, welcome to the podcast. - Hi. Thank you for having me.
- So let's start with the obvious question. What is a dwarfs spheroid
satellite galaxy? - Uh, yeah. So dwarf spheal
galaxies are, uh, galaxies that are much smaller than the
ones we typically think of, like the Milky Way or
the Andromeda Galaxy. Those bright big spiral galaxies. These are thousands of times
smaller, uh, much fainter. Uh, they can have anywhere
from tens to tens of thousands of observable stars. Uh, so much smaller system. Uh, and the al part is the shape. They're just kind of these
faint fuzzy little blobs, small galaxies, uh, and typically observed nearby, uh, in sort of the outskirts of the Milky Way. - How near is near, because
obviously astronomer's definition of what's
near is very different from other scientists. - Uh, so these are all in
our local neighborhood, tens, twenties of kilo pars Xa on the order of maybe tens of light years. Okay. - Okay. And what are you looking for specifically when you're
observing these galaxies? - Uh, so we're using
gamma ray astronomy, uh, specifically the firmat
gamma ray telescope. Uh, and really what we're
looking for is, you know, we know gamma rays come from
various astrophysical sources. So we model the, uh,
astrophysical gamma ray emission that we'd expect to see from gas and dust, supernova,
pulsars, things like that. Um, and then what we're looking for is a little bit more
on top of that, trying to observe something else,
another source of gamma rays that we can't explain with
typical astrophysics in these systems, uh, that we then would say
could be the dark matter. - So why is it it that gamma
rays are a sign of dark matter? What's, what sort of interaction
might be going on there? - Uh, so in, in the theories
that we're testing, uh, the idea is that the dark
matter candidates can undergo a process called annihilation. So you have, uh, a dark matter particle and it interacts with
another dark matter particle, and they destroy each other
anytime they come in contact. Uh, and gamma rays are just
one of many different, uh, standard model particles,
you know, particles that we're familiar with that we can produce in this interaction. Uh, so you can get things
like electrons, protons, but gamma rays are really nice because they're created
immediately at the site of the annihilation event and they travel directly
from the annihilation site to us electrons. If they're created, they're
gonna travel throughout space, they're gonna spread out. Uh, whereas the gamma rays,
you get a nice bright signal and you can trace it
directly back to its source. - Okay. So why is it that, that these dark matter particles
are, are thought to sort of produce a gamma ray
signal in the first place? - So this is gonna be
model theory dependent. So the, the class of particles we're looking
at are called weekly interacting massive particles. Uh, when it comes to dark
matter, we know certain things and it can't have high charge. It can't be, uh, super relativistic
like photons or things. So that kind of narrows the theory space. And these, these weekly
interacting massive particles or wis as they're called,
are a class of particles that reproduce The amount of
dark matter we know exists also allow us to have some observable,
uh, testable hypothesis. So, you know, if somebody
predicts a theory of dark matter, but it doesn't produce anything that no observable predictions,
it's not very helpful for an experimentalist. Um, so these are very enticing
candidate particles, uh, because they reproduce
the known dark matter and they, uh, support these
observational techniques. - And why focus on this
particular type of galaxy? What is, I mean, isn't there
dark matter everywhere? Aren't these an annihilation
events happening, you know, pretty much anywhere you look? - Uh, yeah, absolutely. So what makes the d steroidals
particularly intriguing? Targets? Uh, one, they're,
they're very nearby compared to distant galaxies. The next plus is galaxy to us is the Andromeda
Galaxy, for instance. That's about 800 kilo parts X away. Whereas some of these I've
mentioned are on the order of tens, um, so much closer. Uh, they're also just
loaded with dark matter. Uh, they don't have a lot of of gas, so they don't have a lot of supernova going on, things like that. That's contamination for us. So they're mainly dark
matter, really dense nearby. Uh, and this allows for ideally
a, a nice clean signal, uh, compared to looking at,
uh, galaxies with a ton of astrophysical gamma ray emission. - How do we know that these, uh, um, dwarf sphe are actually
loaded with dark matter? - Right? So this is, uh,
obviously a huge key point of when we're selecting targets. It's how much dark matter do
these systems actually have. So some viewers might be familiar with like galactic rotation curves where dark matter was discovered, right? You look at how stars move in the systems and this allows you to measure how much mass is in the system. Um, and we do the same thing with dwarfs. We measure the, the velocities of stars as they're distributed about. Uh, and this tells us how much
mass is there in dark matter. And, you know, comparing that with how much luminous matter
stars mainly, uh, that we see, we can get a good idea of how
much dark matter is there. And again, these systems are
loaded with dark matter over, you know, 80% of their mass comes in
the form of dark matter. - Okay? So you're looking for gamma rays, and these gamma rays might
come from a particular type of dark matter candidate annihilating, and you're focusing on
the dwarf steroid galaxy 'cause they're nearby and
they're thought to be good candidates for these types of
decays if they, if they exist. So you did a study recently and you found, you found
something, what did you find? - Right. So, you know,
typically these studies, what we're looking for, as I
said, is, uh, that little bit of extra admission compared
to to the backgrounds. Um, and previous studies that have taken, you
know, the same approach. Typically what you find is, uh,
there's nothing else on top. Uh, and so what we do is
you say we can rule out some parameter space. We can put some constraints on the models. Uh, and we do that here. We
put some of the most cons, stringent constraints yet on
these models ruling out saying, okay, it can't be wimps
with this type of mass or this type of annihilation rate. Uh, but in this paper also,
interestingly what we did was, uh, we saw actually there is a little bit of signal that we're seeing. We're seeing a little bit, uh, in excess of the typical astrophysical
models that we've seen. Now at this stage, it's not
at a a, a high enough level that we, uh, can confirm, you know, have the, have the big news. Um, but compared to what's
been seen in the past, uh, we are seeing that that signal is starting to be extracted from the background, uh, which is very exciting for us. - How big a signal are we talking about? - Uh, so this is in, in the paper. This is a, a two sigma signal
above excess, um, and science. We'd like to get that
to at least a five Sigma before we can really
claim it as a big signal. Previous studies haven't even
typically reported high, uh, even up to two Sigma before. So looking forward, you know,
to get to that five Sigma, we probably need at least,
you know, 10 more years of, of data from our telescopes. - So what, why is it that
you need that much more data? What, what, how do you know that you need that much more data? - So one of the things we do
in this paper actually is, uh, we look back at sort of a
historical view of these studies that have been done, um, and see how much we've
improved as data is collected. Um, and so we can see how the data collection
improves our constraints. Looking at that, we can
also make projections, see how well those previous projections worked and make projections into the future based on data collection. Right? As we collect more data, we can still model our background well, but now we're getting more and more emission from,
from our signal source, which would be the dark matter. Uh, we are also looking forward, we'll be getting larger numbers of these dwarf zero galaxies. That's another huge component
is we want to be able to have a large sample size because we're, uh, combining observations
from all these systems. In our paper, we did
50 in the near future, there's some new, uh, optical telescopes that are coming on big large
scale surveys, uh, with some of the most advanced optical telescopes and cameras that we've seen
that can bring that number of 50 dwarfs up to maybe 150, 200. So in addition to collecting
extra gamma ray information, uh, we'll also be in increasing the sample size of dwarfs that we can look at. - And supposing this two Sigma sig is, does turn out to be real. I know we're getting ahead
of ourselves a little bit, but what would that tell us about dark matter? If it is real? - Uh, right. So if this
signal is real, you know, that that'll be a
process in the future to, to really nail that down. Um, but what it would
tell us is that we have a excellent specific candidate for what the dark matter could be, right? We'd be able to say it's a, a wimp a wimp with specific mass. Uh, in this paper we were
looking at about a 200 GEV range, which is about 200 times,
uh, the mass of a proton. Uh, so we'd be able to
say, if we got this signal to a Five Sigma or something like that, here is a very strong candidate because we've looked
at these clean systems and we have a significant signal. Um, and what that would
lead really is to the rest of the scientific community following up and looking at different probes
of dark matter to see, okay, can we confirm this from
different angles now? Uh, can we say this dark
matter particle make other predictions about, uh, what
we might be able to see with other experiments? And then if it turns out to be
dark matter coming from those other complimentary probes,
uh, then obviously that's huge because this is one of the
largest outstanding pro uh, problems in astrophysics. - Yeah. 'cause a lot of
the, the experiments to try to find dark matter are, are whether they're
based in earth actually, and they're, they're
sort of big detectors, maybe buried underground,
maybe having lots of, uh, you know, exotic materials involved. Um, you know, would anything,
are any of those, those sort of existing detectors, would they be able to see this signal? Have you sort of compared back and forth between the astrophysics side and the particle physics side? Uh, - Yeah. So the, these particle base or these ground-based, uh,
detectors on earth, um, they also look for this
class of particles. Um, the, the Wims have for
a long time been a, uh, kind of a, a leading well-motivated candidate. Uh, so they're absolutely looking for it. And, you know, whether
their capabilities would get to the point to see it directly. Uh, it is a little hard
to say at this stage, but I think, I think they
definitely could, uh, you know, those are very advanced instruments, very, uh, powerful tools. Um, but it, it would
certainly help, you know, with our work, if we can confirm a a, a five Sigma specific particle,
they can kind of hone in and, and test specifically
that model, um, and, and see if they can see it again. I think, you know, this, uh,
technique that we use, uh, looking at for the annihilation signal and in gamma race is putting
some of the tight, has put some of the tightest constraints on models. Uh, and only now are we starting to see really something there. Um, so I, I think they'll need some time to, to catch up to that. But certainly with a, a specific
model in mind, they could, uh, start to probe that as well and, and see if they can see it. - It narrows down the,
it makes the haystack. They're looking in smaller, I guess. - Exactly. Exactly.
- Yeah. And you talk about this being a sort of like 10 year project to find more data. Are you gonna be involved in that? What are your plans for the future? - Uh, so I'm currently now, uh, I've, I've finished up my postdoc at Clemson. Now I'm working in, uh, a
field outside of academia and astrophysics and, and finance and specifically data scientists. Um, so taking those same data
analysis skills that, uh, helped us put these interesting
constraints on this and, and potentially find a signal, um, and, and taking that to a new field. So I've left my, uh, excellent colleagues
on the paper in charge of updating me in 10 years
if this is dark matter or not. Uh, so we'll see. - Alex Aniel, thank you very much. - I'm afraid that's all the time we have for this week's podcast,
which is sponsored by Racon Vacuum Instruments. Thanks to Lily Ellis,
Gibbons, Alex McDaniel and Margaret Harris for joining me today. And a special thanks to
Callum Gel, our producer. We'll be back again next week. Thon Vacuum Instruments provides all types of vacuum metrology for a
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